1. The Field of the Invention
The present invention relates generally to an instant engagement, bearing-type clutch, particularly well suited for use with a wrench. More particularly, the present invention relates to a switching mechanism for such a clutch or wrench.
2. The Background Art
Various types of fasteners are used to attach two or more members together. A bolt and nut combination is one type of well known fastener. The bolt includes a male threaded end configured to engage a female threaded nut.
The driving end of the bolt, or the head, and the nut are provided with bodies of standard size and shape. The most common shape is a hexagon, or six-sided body. Other shapes are available, including a square. The head may also be provided with a hole or bore of standard size and shape. Such shapes include various stars with straight and curved sides and various polygons. In addition, such heads and nuts are provided in English and metric size ranges, such as xe2x85x9 in., {fraction (3/16)} in., xc2xc in., {fraction (5/16)} in., xe2x85x9c in., etc., or 3 mm, 4 mm, 5 mm, 6 mm, etc.
Special tools are configured to engage and drive either the head of the bolt and/or the nut. For example, a wrench typically has an open-ended jaw and a closed-ended jaw. The ends are sized and configured to mate with the bolt head or nut. Thus, wrenches typically have apertures formed in the ends with various polygonal shapes, or stars with various numbers of points. In addition, the wrenches are usually provided in sets having numerous wrenches each having jaws configured to mate with a particularly sized bolt head or nut. By engaging the bolt head or nut with the appropriate wrench, the bolt or nut may be rotated clockwise or counterclockwise in order to tighten or loosen the fastener, respectively.
One problem with the above described wrenches is that they often must be continually disengaged and re-engaged with the nut or bolt. Often, a fastener is placed adjacent another member or located in a limited space. Because the wrench has an elongated body, it may be turned only a fraction of the necessary rotation before any further rotation is impeded. Thus, the wrench must be disengaged from the head, rotated back to the starting point, re-engaged with the head, rotated until again impeded, and the process repeated until the fastener is either loosened or tightened. In addition, if the head is located where only a small rotation is possible, the wrench must also be turned over after disengaging because the handle extends at an angle from the end of the wrench. Furthermore, if the space is extremely tight, the wrench may be rendered useless because there is insufficient space in which the wrench may turn the head.
A ratchet wrench is very popular and solves many of the above identified problems with the standard wrench. The ratchet wrench has a ratchet mechanism which allows a handle of the wrench to rotate freely in one direction, but engage a driver coupled to a head of the ratchet wrench in the opposite direction. This allows the ratchet wrench to engage a head, and rotate back and forth, tightening or loosening the fastener without having to disengage the wrench from the head.
The typical ratchet wrench has an elongated body with a head adapted to receive sockets of various sizes and shapes. Thus, sockets usually are provided in sets with one or more ratchet wrenches. The ratchet wrench typically has a set of teeth formed on a driver portion and a pawl which engage in one direction.
One problem with the ratchet wrench is the finite increments the wrench may be rotated backwards. Conventional ratchet wrenches have a finite number of engagement points and are therefore limited in the degree they may be rotated backwards by the number of the teeth. For example, if there are 60 teeth, the ratchet wrench is limited to 6 degree increments when rotating backwards before another tooth can be engaged. If the head of the bolt is located in a tight space, it may not be possible to rotate the ratchet wrench a full 6 degrees. Thus, the wrench will not be able to rotate back more than the 6 degrees to engage the next tooth, rendering the wrench useless.
In addition, center-switching ratchet wrenches often have a dial or switch for operating the direction of the wrench. Such switches typically operate in a standard manner. For example, turning the switch of a typical ratchet wrench counter-clockwise results in the wrench and socket turning together in the clockwise direction (such as to tighten), and turning freely in the counter-clockwise direction. Similarly, turning the switch of a typical ratchet wrench in the opposite direction, or clockwise, results in the wrench and socket turning together in the counter-clockwise direction (such as to loosen), and turning freely in the clockwise direction. It will be appreciated that typical users of such ratchet wrenches have become accustom to the standard operation of the ratchet wrench, and expect similar operation or control from all wrenches.
It has been recognized that it would be advantageous to develop a wrench with an infinite number of engagement points, or a wrench that instantly engages despite the amount of backwards rotation. It also has been recognized that it would be advantageous to develop such a wrench capable of operation in both directions, or a reversible wrench. It also has been recognized that it would be advantageous to develop a reversible clutch capable of instantaneous engagement and with infinite increments in the reverse direction. It also has been recognized that it would be advantageous to develop such a wrench that operates, or has controls that operate, similarly to common ratchet wrenches.
The invention provides a wrench device having a bearing clutch device. The device includes a secondary body rotatably coupled to a primary body, and defining a tapering space therebetween. At least one bearing is movably disposed in the tapering space, and is movable between a free location, and a binding location in which the at least one bearing lodges between the primary and secondary bodies. A displacement member is movably disposed in the tapering space, and is engagable with the at least one bearing to dislodge the at least one bearing from the binding location to the free location. A switch is pivotally disposed on the secondary body.
The displacement member pivots clockwise, causing the primary and secondary bodies to bind in the clockwise direction, and rotate freely in the counterclockwise direction. Similarly, the displacement member pivots counterclockwise, causing the primary and secondary bodies to bind in the counterclockwise direction, and rotate freely in the clockwise direction.
In accordance with one aspect of the present invention, the device advantageously includes means for moving the displacement member in an opposite direction to a pivoting direction of the switch. Thus, the wrench device of the present invention has a switch that operates in the same rotational direction as traditional, center-switching, ratchet wrenches.
For example, the switch can pivot counterclockwise, causing the primary and secondary bodies to bind in the clockwise direction, such as to tighten. Similarly, the switch can pivot clockwise, causing the primary and secondary bodies to bind in the counterclockwise direction, such as to loosen.
In accordance with another aspect of the present invention, the wrench device can include a pivot member disposed between the displacement member and the switch. The pivot member engages both the displacement member and the switch. Thus, pivoting the switch in one direction results in movement of the displacement member in the opposite direction.
In accordance with another aspect of the present invention, the wrench device can include a gear pivotally disposed between the switch and the displacement member. The gear can have teeth engagable with teeth formed on the displacement member and teeth formed on the switch. Thus, pivoting the switch in one rotational direction results in movement of the displacement member in an opposite rotational direction.
In accordance with another aspect of the present invention, the displacement member can include a ring pivotally disposed with respect to the primary body and the tapering space. The at least one pin can extend from the ring into the tapering space. In addition, the teeth of the displacement member being formed on the ring.
Additional features and advantages of the invention will be set forth in the detailed description which follows, taken in conjunction with the accompanying drawing, which together illustrate by way of example, the features of the invention.